VW T25 i987 Crew cab starting issues

[Drawl21]

Hi all,new to the forum,and 1st post,i have a 1987 T25 doka/crew cab,its a 1.6 N/A diesel,with a JP code(Mk2 golf,i think?)engine in it,when i turn on the ignition the glow plug light on the dash only stays on for 3 seconds,its not freezing here in Manchester,but still cold in a morning,it cranks over for quite a while,when it does start i get clouds of white smoke,that goes after a minute and she runs and revs nicely,if i turn her of she starts 1st turn of the key with no smoke,i know there's a glow plug temp sensor at the rear of the cyl head,a glow plug relay and glow plugs,but i'm new to diesels,any ideas on how and what i should be checking first?,thanks for any replies,cheers Dave

[vanbcguy]

First test I'd do would be to unplug the temperature sensor. Once you do that the GP relay should keep the GPs on for the full cycle. If the light still goes out quickly you probably have a bad GP relay. If the light stays on for a long time you may have a bad temp sender. Make sure you're unplugging the correct sensor - there is usually one for the gauge, one for the GPs and sometimes one for the AC. Some later cars have a 4 pin sensor which has both the gauge and glow plug sensor in one.

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[Drawl21]

Thanks for the reply,I'll check that tomorrow,cheers Dave

[rallye_golf]

I would check the actual glow plugs are working. You can check the resistance of each one with a mulitmeter, I prefer to take them out and check them using a battery and a piece of wire, put the body on the negative terminal, and use the wire from positive terminal to the connector on top. it should glow red hot at the tip.
For what they cost it might be just as well to replace them. Use genuine quality ones though, cheaper ones don't last very long.

[Drawl21]

Thanks,was thinking about that too,only thing putting me off is the one under the pump,its supposed to be a pain isn't it?,what manufacturers glow plugs should i be looking at?,i tried taking the wire off the glow plug temp sensor,it made no difference to the yellow light on the dash,still only on for 3 secs tops,i'll order a relay and sender today,if it makes no difference,i'll bite the bullet and have a go at the plugs,i'll report back when i've fitted the relay and sender,thanks for all replies,Cheers Dave

[vanbcguy]

Bosch Duraterms are the only plugs to even consider.

I wouldn't replace them "just because" personally. You don't need to yank them to verify if they are working either, just cycle them on a cold engine then touch the terminal end - it should be warm. If not the GP isn't working.

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